Add OnKey support for DA9063

From: Steve Twiss <[email protected]>

Add device tree bindings for the DA9063 OnKey driver

Signed-off-by Steve Twiss <[email protected]>

---
Version History

Changes in V4
- No change

Changes in V3
- No change

Changes in V2
- Remove the circular dependency comment linking patches in the main e-mail
- Search and replace 'keyword' with 'property' in onkey sub-node description
- Reformat onkey sub-node content to move the description for key-power into a new optional properties sub-section so it has a more promiment position

This patch applies against linux-next and v4.1-rc3

 Documentation/devicetree/bindings/mfd/da9063.txt | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

Documentation/devicetree/bindings/mfd/da9063.txt +18 -0

index 42c6fa6..05b21bc 100644
@@ -5,6 +5,7 @@ DA9093 consists of a large and varied group of sub-devices (I2C Only):
 Device                   Supply Names    Description
 ------                   ------------    -----------
 da9063-regulator        :               : LDOs & BUCKs
+da9063-onkey            :               : On Key
 da9063-rtc              :               : Real-Time Clock
 da9063-watchdog         :               : Watchdog
 

@@ -51,6 +52,18 @@ Sub-nodes:
   the DA9063. There are currently no entries in this binding, however
   compatible = "dlg,da9063-rtc" should be added if a node is created.
 
+- onkey : This node defines the OnKey settings for controlling the key
+  functionality of the device. The node should contain the compatible property
+  with the value "dlg,da9063-onkey".
+
+  Optional onkey properties:
+
+  - dlg,disable-key-power : Disable power-down using a long key-press. If this
+    entry exists the OnKey driver will remove support for the KEY_POWER key
+    press. If this entry does not exist then by default the key-press
+    triggered power down is enabled and the OnKey will support both KEY_POWER
+    and KEY_SLEEP.
+
 - watchdog : This node defines settings for the Watchdog timer associated
   with the DA9063. There are currently no entries in this binding, however
   compatible = "dlg,da9063-watchdog" should be added if a node is created.

@@ -73,6 +86,11 @@ Example:
 			compatible = "dlg,da9063-watchdog";
 		};
 
+		onkey {
+			compatible = "dlg,da9063-onkey";
+			dlg,disable-key-power;
+		};
+
 		regulators {
 			DA9063_BCORE1: bcore1 {
 				regulator-name = "BCORE1";

From: Steve Twiss <[email protected]>

Add MFD support for the DA9063 OnKey driver

The function da9063_clear_fault_log() is added to mitigate the case of a hardware power-cut after a long-long OnKey press. Although there is no software intervention in this case (by definition) such a shutdown would cause persistent information within the DA9063 FAULT_LOG that would be available during the next device restart.

Clearance of this persistent register must be completed after such a hardware power-cut operation has happened so that the FAULT_LOG does not continue with previous values. The clearance function has been added here in the kernel driver because wiping the fault-log cannot be counted on outside the Linux kernel.

Signed-off-by Steve Twiss <[email protected]>

---
Version History

Changes in V4
- Additional description of MFD patch changes for FAULT_LOG in relation to the requirements of the OnKey driver. Please see a further explanation of the OnKey's operation in this thread: https://lkml.org/lkml/2015/4/29/406

Changes in V3
- The MFD code was originally in [PATCH V2 1/2]. This is now been moved into this patch [PATCH V3 3/3].
- Whitespace cleanup

This patch applies against linux-next and v4.1-rc3

 drivers/mfd/da9063-core.c        | 54 ++++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/da9063/pdata.h |  1 +
 2 files changed, 55 insertions(+)

drivers/mfd/da9063-core.c +54 -0

index facd361..af841c1 100644
@@ -60,6 +60,7 @@ static struct resource da9063_rtc_resources[] = {
 
 static struct resource da9063_onkey_resources[] = {
 	{
+		.name	= "ONKEY",
 		.start	= DA9063_IRQ_ONKEY,
 		.end	= DA9063_IRQ_ONKEY,
 		.flags	= IORESOURCE_IRQ,

@@ -97,6 +98,7 @@ static const struct mfd_cell da9063_devs[] = {
 		.name		= DA9063_DRVNAME_ONKEY,
 		.num_resources	= ARRAY_SIZE(da9063_onkey_resources),
 		.resources	= da9063_onkey_resources,
+		.of_compatible = "dlg,da9063-onkey",
 	},
 	{
 		.name		= DA9063_DRVNAME_RTC,

@@ -109,12 +111,64 @@ static const struct mfd_cell da9063_devs[] = {
 	},
 };
 
+static int da9063_clear_fault_log(struct da9063 *da9063)
+{
+	int ret = 0;
+	int fault_log = 0;
+
+	ret = regmap_read(da9063->regmap, DA9063_REG_FAULT_LOG, &fault_log);
+	if (ret < 0) {
+		dev_err(da9063->dev, "Cannot read FAULT_LOG.\n");
+		return -EIO;
+	}
+
+	if (fault_log) {
+		if (fault_log & DA9063_TWD_ERROR)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_TWD_ERROR\n");
+		if (fault_log & DA9063_POR)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_POR\n");
+		if (fault_log & DA9063_VDD_FAULT)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_VDD_FAULT\n");
+		if (fault_log & DA9063_VDD_START)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_VDD_START\n");
+		if (fault_log & DA9063_TEMP_CRIT)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_TEMP_CRIT\n");
+		if (fault_log & DA9063_KEY_RESET)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_KEY_RESET\n");
+		if (fault_log & DA9063_NSHUTDOWN)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_NSHUTDOWN\n");
+		if (fault_log & DA9063_WAIT_SHUT)
+			dev_dbg(da9063->dev,
+				"Fault log entry detected: DA9063_WAIT_SHUT\n");
+	}
+
+	ret = regmap_write(da9063->regmap,
+			   DA9063_REG_FAULT_LOG,
+			   fault_log);
+	if (ret < 0)
+		dev_err(da9063->dev,
+			"Cannot reset FAULT_LOG values %d\n", ret);
+
+	return ret;
+}
+
 int da9063_device_init(struct da9063 *da9063, unsigned int irq)
 {
 	struct da9063_pdata *pdata = da9063->dev->platform_data;
 	int model, variant_id, variant_code;
 	int ret;
 
+	ret = da9063_clear_fault_log(da9063);
+	if (ret < 0)
+		dev_err(da9063->dev, "Cannot clear fault log\n");
+
 	if (pdata) {
 		da9063->flags = pdata->flags;
 		da9063->irq_base = pdata->irq_base;

include/linux/mfd/da9063/pdata.h +1 -0

index 95c8742..612383b 100644
@@ -103,6 +103,7 @@ struct da9063;
 struct da9063_pdata {
 	int				(*init)(struct da9063 *da9063);
 	int				irq_base;
+	bool				key_power;
 	unsigned			flags;
 	struct da9063_regulators_pdata	*regulators_pdata;
 	struct led_platform_data	*leds_pdata;